local and site level effects on nesting barn swallows€¦ · Stage 3 is the addition of a grass...

Local and site-level effects on nesting Barn Swallows

A Major Qualifying Project

submitted to the Faculty

of the

WORCESTER POLYTECHNIC INSTITUTE

in partial fulfillment of the requirements for the Degree of Bachelor of Science

By:

_______________________________

Mariah Eldredge

And

_______________________________

Margaret Hester

Approved By:

_______________________________

Marja Bakermans, Advisor

ii

Table of Contents Table of Contents ........................................................................................................................... ii

Table of Figures ............................................................................................................................. iii

Table of Tables ............................................................................................................................... iv

Abstract ............................................................................................................................................ v

Introduction ..................................................................................................................................... 1

Methods ........................................................................................................................................... 7

Results ........................................................................................................................................... 11

Discussion ...................................................................................................................................... 16

Literature Cited .............................................................................................................................. 21

Appendix A: Comprehensive Nest Data ....................................................................................... 24

Appendix B: Comprehensive Descriptive Statistics ...................................................................... 30

iii

Table of Figures Figure 1: Barn Swallow identification guide. .................................................................................. 3

Figure 2: Reused Barn Swallow mud-cup nest made with straw. ................................................... 4

Figure 3: Barn Swallow incubating her. .......................................................................................... 5

Figure 4: Active and control locations. ........................................................................................... 8

Figure 5: Human activity frequency and Barn Swallow nest presence. ........................................ 14

Figure 6: Comparison of Barn Swallow nest presence and competitor species presence with

standard error bars. ................................................................................................................ 16

iv

Table of Tables Table 1: Daily survival probability and potential factors influencing nest success. ..................... 12

Table 2: Data used for MANOVA. ............................................................................................... 13

Table 3: Spearman correlation data (n=10). .................................................................................. 15

Table A- 1: Site locations and characteristics. .............................................................................. 24

Table A- 2: Nest success descriptive data. .................................................................................... 27

Table A- 3: Comprehensive nest success summary. ..................................................................... 27

Table A- 4: Individual nest success. .............................................................................................. 28

Table B- 1: Visit summary descriptive statistics. .......................................................................... 30

Table B- 2: Additional visit summary statistics. ........................................................................... 31

Table B- 3: Visit summary predator sighting statistics. ................................................................ 32

v

Acknowledgements We would like to thank our advisor, Marja Bakermans, for all of the support and

guidance she provided on this project. We would also like to thank all of the people who allowed

us onto their property and into their barns and sheds. Without willing homeowners, our project

would not have been possible.

1

Abstract Aerial insectivore populations have been declining, and the reason for decline is unclear. There is

recent concern over Barn Swallow (Hirundo rustica) populations, an aerial insectivore species,

due to conflicting findings in current populations. We observed 20 sites in Harvard and

Falmouth, Massachusetts from May through July, 2013 to identify factors that influenced site

selection and nest success to improve understanding of Barn Swallow breeding behavior. Our

data suggest that human activity can determine whether a site is selected for nesting, and that the

presence of Eastern Phoebes (Sayornis phoebe) and European Starlings (Sturnus vulgaris) can

affect Barn Swallow nest success.

Introduction We can never have enough of nature. Henry David Thoreau, Walden

Without aerial insectivores, the food chain would collapse. Aerial insectivores are

organisms with the ability to fly who consume insects in the air. Examples of aerial insectivores

include bats and some species of birds. Aerial insectivore populations have been declining,

particularly migratory birds of North America’s northeast, and the reason for the decline in

population is unclear (Nebel et al. 2010). Some researchers believe acid rain or increased

pesticide use reduces insect populations in breeding ranges, thus limiting predator populations

(Connecticut Audubon Society 2013). Others believe that shifts in insect populations across

migration paths limit the populations of migratory insectivores, who maintain their flight routes

regardless of insect relocation (Nebel et al. 2010). Research suggests that humans may also have

an impact; high human population density correlates with more avian species richness, so in

densely human-populated areas, avian competition may be higher (Luck 2007). Since the

2

industrial revolution, combined with population shifts towards cities, there has been a decrease in

farms and barns, which has been linked to a decrease in Barn Swallow abundance (Moller 2001).

Barn Swallows, Hirundo rustica, are a common species of aerial insectivore whose populations

are considered at risk in New England, and are the focus of this study.

Although considered an at risk species, Barn Swallows are an abundant and widespread

swallow species (Massachusetts Audubon Society 2011). Barn Swallows live worldwide, and

can be found across the United States and most of Canada during the summer for breeding

season, and found year round in parts of Central America. Barn Swallows often migrate to

Southern California, Florida, the Caribbean, and some parts of Central America for the winter

(Brown and Brown 1999).

Since the 1800s, Barn Swallows have adapted to using manmade structures for nest sites,

and this has led to an increased range and population size (Newton 1998). However, there is

recent concern over the state of Barn Swallow populations due to conflicting findings in modern

populations. According to the 2011 State of the Birds Report, Barn Swallow populations are

stable but in need of monitoring (Massachusetts Audubon Society 2011). Barn Swallows had a

2.3% increase in population from 1974-1979 according to the Massachusetts Audubon Society’s

Breeding Bird Atlas, despite the Breeding Bird Survey finding a 1.3% decrease in population

from 1966-2011 (Massachusetts Audubon Society 2011).

Barn Swallows can be spotted by the distinctive characteristic of their long, deeply forked

tail, which is a trait found in no other swallow (Fig. 1). Barn Swallows have a blue hue on their

back, wings and tail feathers, which can lead to confusion with Cliff Swallows, Petrochelidon

pyrrhonota, which have similar coloration (Brown and Brown 1999). The tail has white spots,

which are larger in adults, particularly males (Kose and Moller 1998).

3

Figure 1: Barn Swallow identification guide (Pratt 2013).

Monogamous for the breeding season, male and female Barn Swallows work together to

build the nest, with male participation in nest construction varies anywhere from 0-68% (Brown

and Brown 1999). Barn Swallows nest in mud cups, which are made by collecting mud in their

bills and mixing the mud with grass stems or other materials to make pellets (Fig. 2). During the

multistep process, a base is formed, which takes 1-5 days. Next, it takes 3-14 days to construct

the mud shell. Stage 3 is the addition of a grass lining to the mud cup, which takes 1-5 days.

Finally, the nest is complete at stage 4 when the lining of feathers, hair, moss, or other soft

material is added, which takes 1-4 days (Brown and Brown 1999). The mud cups are typically

gourd-shaped (Petersen and Meservey 2003). A complete mud-cup nest has approximately an 8

4

centimeter diameter and a 5 centimeter depth (Brown and Brown 1999). Swallows reuse nests,

and replace the feathers and add a new layer of mud around the rim annually (Brown and Brown

1999).

Figure 2: Reused Barn Swallow mud-cup nest made with straw (Photograph by Mariah Eldredge).

Barn Swallows are often colonial, and tend to return to their nesting grounds year after

year (Brown et al. 2002). Large colonies are usually populated by young birds, and nest success

in the large colonies has been found to be less than that of individual nests or small colonies

(Shields and Crook 1987). However, colonies can also have higher rates of nest success due to

decreased predation and increased social stimulation (Snap 1976). Another possible contribution

to poor nest success in Barn Swallows are House Sparrows, Passer domesticus, a fierce

5

competitor of Barn Swallows. They have been observed stealing nest linings and materials, and

pecking or removing eggs or nestlings (Weisheit and Creighton 1989). Weisheit and Creighton

found that the presence of House Sparrows reduced fledging success by 45% at one Barn

Swallow nesting site in Maryland (Brown and Brown 1999).

Barn Swallows lay 3-7 eggs, and have one to two broods annually (Petersen and

Meservey 2003). They begin laying eggs once the feather lining of the nest has been completed,

one egg per day. The eggs are incubated between 12 and 17 days; both sexes incubate, but the

female takes on most of the responsibility (Fig. 3).

Figure 3: Barn Swallow incubating her eggs (Photograph by Mariah Eldredge).

6

The eggs are a cream to pinkish white color, with spots that can be brown, lavender or gray.

Once hatched, the Barn Swallow nestlings are naked with sparse patches of gray down, and have

their eyes closed. The nesting period for these young birds is 15-27 days (Brown and Brown

1999). When they leave the nest, they have a lighter juvenile coloration (Fig. 1).

Swallows primarily feed on flies, but occasionally catch beetles, bees, wasps, ants,

butterflies, moths and other flying insects (Brown and Brown 1999). Swallows prefer to eat one

large insect over several small insects. Barn Swallows catch their prey while in flight. They fly

low, skimming the ground or water surface where they are searching for food, with fluid

wingbeats that pull their wingtips back at the end of a stroke (Brown and Brown 1999).

The Big Barn Study is a research study being conducted by the Massachusetts Audubon

Society, investigating Barn and Cliff Swallow breeding populations in Massachusetts

(Massachusetts Audubon Society 2012). The study intends to determine why certain sites are

preferred over others, the characteristics of the used sites, and how sites have changed over time.

The Big Barn Study is conducted through citizen science, and volunteers go to barns, bridges,

and other potential nesting sites, observe the site 3 times, and record whether swallows are

present or not. Citizen scientists are also asked to look for house sparrows, swallows’ competitor

(Massachusetts Audubon Society 2012). Our study is supporting the Big Barn Study, and

investigating similar themes.

In our research, we gathered descriptive information about the locations of interest. We

determined the frequency of human activity at each location, as well as distance to open fields,

distance to bodies of water, and presence of livestock. We determined colony size at each

location, and monitored the number of predator and competitor species in the vicinity of nests,

including cats and House Sparrows. The goal of our research was to determine whether 1) there

7

is a difference between sites with Barn Swallow nests and sites without Barn Swallow nests and

2) factors such as colony size and competitor species presence affect Barn Swallow nest success.

We hypothesized that there would be a difference between used and unused sites; we anticipated

that barns and other structures that were close to bodies of water and open fields would be used

more frequently than structures far from bodies of water and open fields. We also hypothesized

that the presence of predator or competitor species would negatively affect nest success, and

large colonies would positively affect nest success.

Methods Study area.- Our study was conducted in the Harvard, Massachusetts area and Falmouth,

Massachusetts areas because they have many bodies of water near open fields, which are ideal

habitats for aerial insectivores due to food availability. Both towns are historically farming

communities, and today still have many small farms, barns, and stables. These regions also have

large land areas owned by conservation groups.

Field methods.- We visited and observed nesting sites every three to five days until nest success

was determined, May 15 through August 18, 2013. Using the Massachusetts Audubon Society’s

Big Barn Study as a model, we monitored five active Barn Swallow nesting sites in each region,

as well as 5 locations in each region with no swallows present. The active locations were homes

of volunteers who had observed Barn Swallows on their properties (Figure 4). We determined

the locations with no swallows present by randomly selecting locations in the study areas that are

optimal swallow nesting sites, such as barns, overpasses, and bridges. We checked the sites with

no swallows present three times each, and they were used as controls to determine if there is a

significant difference between sites with Barn Swallow nests and those without.

8

Figure 4: Active and control locations. Red markers are locations with active Barn Swallow nests, and blue markers are control locations (Maps by Google Maps). At each test site we counted the number of nests, identified the structure on which they

were built, and measured geographical characteristics of the nest area. Some of the geographical

9

characteristics included distance in meters to fields, bodies of water, and wooded areas. We also

quantified the amount of daily human activity causing a disturbance at each location, as follows:

1) No daily human activity

2) Some daily human activity (humans around nest once or twice per day)

3) Frequent daily human activity (humans around nest three times per day or more)

We monitored the status of each nest. Status was identified with a numbered code, as

follows:

1) Nest appears active

2) Nest has eggs, female actively incubating

3) Nest has eggs, female flushed

4) Nest has eggs, female not present

5) Nest has hatchlings

6) Nest has fledglings

7) Nest failed, most likely predation

8) Nest failed, unknown causes

9) Other (identify)

If it was possible to determine, depending on the height of the nest, we counted the number of

eggs or young birds. Finally, we looked for other species in the area that can influence nesting

location and success for Barn Swallows. The species that we looked for were European Starlings

(Sturnus vulgaris), Eastern Phoebes (Sayornis phoebe), House Sparrows, and Brown-headed

cowbirds (Molothrus ater), as well as predators such as birds of prey and cats and other

terrestrial predators. These species could all have an effect on nest success, whether due to brood

parasitism, nest competition, or predation.

Data analysis.- To determine the percentage of overall nest success, we used a ‘traditional

method’ which divides the number of successful nests by the number of total nests found (Jehle

et al. 2004). To compare the daily survival probability in different nest locations, we used the

10

Mayfield Estimator (Garaldi 2006). We calculated the daily survival probability at each site, and

compared the survival rates of sites with different characteristics. By comparing the daily

survival probability of different nest locations, we drew preliminary conclusions about which

locations lead to higher nest success.

To identify whether there is a significant difference between sites with Barn Swallow

nests and those without Barn Swallow nests, we conducted a multivariate analysis of variance

(MANOVA), based on distance of structure to body of water and distance of structure to open

field. A chi-squared test was used to determine the difference between sites with Barn Swallow

nests and sites without Barn Swallow nests based on the presence of livestock. The null

hypothesis was that there is no difference between sites with and sites without Barn Swallow

nests in terms of the presence of livestock. We used a chi-square test to determine whether

human activity at a location affects Barn Swallows nest site selection, using a null hypothesis

that human activity has no impact on whether a site is selected for Barn Swallow nesting.

We used an analysis of variance (ANOVA) to compare a surrogate of nest success, mean

number of fledglings at each site, to the mean number of House Sparrows observed in the area of

active nests, mean number of European Starlings in the area of active nests, mean number of

Eastern Phoebes in the area of active nests, and colony size to determine if these factors affect

nest success. We used a Bonferroni correction to avoid Type I error caused by comparing

multiple potential variables (Bland and Altman 1995). Because we used 4 tests, we divided our

“normal” p-value by 4, resulting in a new p-value of 0.0125. We used a correlation analysis to

determine if these variables were correlated. Because our data were non-normal we used a

Spearman correlation analysis.

11

Results We monitored 55 Barn Swallow nests from May 15-July 18, 2013, and 48 nests were

successful (87.27%). The mean number of days for a nest to be active was 36.15 (6.21 SE,

standard error). The mean number of fledglings from each nest was 4.06 (0.25 SE). For

additional nest and nest success data, refer to appendix A.

Predators (i.e., cats, dogs, and hawks) present at each site were recorded, but because

there were not many predators and no predation events observed, predator data were not

considered for further analysis (Table 1). Human activity, competitor species (House Sparrows

(HOSP), European Starling (EUST), Eastern Phoebe (PHOE)) present at each site, and colony

size were also recorded (Table 1). We also calculated the daily survival probability, or Mayfield

Estimate (Table 1). For further descriptive statistics and individual nest success data, refer to

appendix B.

After conducting the MANOVA analysis, we determined that there is no significant

difference in sites with or without Barn Swallow nests when considering distance to body of

water or open field (Wilks' Lambda F2,17 = 0.64, P = 0.54). The data used in this calculation can

be found in table 2. For sites with Barn Swallow nests, the distance we measured to water ranged

from 22 meters to 914 meters. The average distance to water at sites with nests was 201.2 meters.

For sites without Barn Swallow nests, the distance to water ranged from 64 meters to 1322

meters. The average distance to water at sites without nests was 249.2 meters. For sites with

Barn Swallow nests, we measured distance to field ranging from 8 meters to 49 meters. The

average distance to a field at sites with nests was 21.2 meters. For sites without Barn Swallow

nests, distance to a field ranged from 3 meters to 75 meters. The average distance to water at

sites without nests was 29 meters.

12

Table 1: Daily survival probability and potential factors influencing nest success.

Location Number of nests

Daily Survival

Probability (Mayfield Estimate)

Mean # Observed

Cat

Mean # Observed

Hawk

Mean # Observed

Dog

Human activity rating

Mean # Observed

HOSP

Mean # Observed

EUST

Mean # Observed

PHOE

Colony Size

Saafield's Barn 6 1 0 0 0 2 0.39 0.06 0.67 6

Micheldever Farm 5 1 0 0 1 2 5.36 0 0.64 5

Post Office 3 0.99 0 0 0 3 0.05 0.24 0 3

Stable 1 1 4.77 0 0 3 1.85 0 0 1

Flintlock Farm 18 1 0 0 0 2 0 0 0.07 18

Coonamessett Farm 2 1 0 0 0 3 12.38 0.75 0.25 2

Crooked Pond Farm 5 1 0 0 0 2 0 0 0 5

Boxberry Farm 1 1 0.78 0 0.78 3 3.11 0 0 1

Smithfield Farm 2 0.98 0.18 0 2.27 3 4.09 0 0 2

Maushop 12 0.99 0 0 1.4 2 10.7 0 0 12

13

Table 2: Data used for MANOVA.

Location Swallow Nests?

Distance to water

(m)

Distance to field

(m) Human activity

Livestock present?

Saafield's Barn Yes 27 20 2 No Micheldever Farm Yes 27 8 2 Yes Post Office Yes 44 16 3 No Stable Yes 49 13 3 Yes Flintlock Farm Yes 22 11 2 No Coonamessett Farm Yes 74 24 3 yes Crooked Pond Farm Yes 161 16 2 yes Boxberry Farm Yes 550 21 3 yes Smithfield Farm Yes 914 34 3 yes Maushop Yes 144 49 2 yes Dunroven Farm No 142 17 3 Yes Fruitlands No 1322 13 1 No Still River Farm No 146 19 3 Yes Glimerton Farm No 115 15 3 Yes Bazarnick's House No 64 3 2 No Nyes Neck Farm No 212 41 2 No Grove Barn No 140 58 3 No Old Storage Shed No 161 75 2 No Farm Storage Shed No 75 34 2 Yes Play Shack No 115 15 3 Yes

We found no evidence that presence of livestock influenced nest selection by Barn

Swallows (χ2=0.80, P= 0.15). Of the 10 sites with Barn Swallow nests present, 7 sites had

livestock present as well. The Post Office, Flintlock Farm, and Saafield’s Barn did not have

livestock present. We did find evidence that occasional to frequent human activity influences

Barn Swallow nest site selection (χ2=0.83, P= 0.03). Locations with human activity ratings of 2

or 3 were the locations with Barn Swallow nests (Fig. 5).

14

Figure 5: Human activity frequency and Barn Swallow nest presence.

Based on the ANOVA, considering the Bonferroni adjustment, there is a significant

difference in number of fledglings when European Starlings (F2,9 = 4.41, P < 0.001) or Eastern

Phoebes (F2,9 = 4.41, P < 0.001) were observed in the area of Barn Swallow nests. When

European Starlings were sighted more often, we found that there were fewer Barn Swallow

fledglings; there is a slightly negative relationship (Figure 6). Conversely, there was a slight

positive relationship between Eastern Phoebe sightings and number of fledglings (Figure 6). The

Spearman correlation did not find that the relationship between number of fledglings and

presence of competitor species was significant (Table 3).

0

1

2

3

4

5

6

1 2 3

Num

ber of Sites

Human Activity Frequency Rating

Number of Sites with Barn Swallow Nests

Number of Sites Without Barn Swallow Nests

15

Table 3: Spearman correlation data (n=10). Mean Fledges Mean HOSP Mean EUST

Mean HOSP -0.46

Mean EUST -0.13 0.13

Mean PHOE 0.15 0.14 0.39

Colony Size 0.43 -0.27 0.39

Figure 6: Comparison of number of competitor species (European Starling, EUST and

Eastern Phoebe, PHOE) sightings and number of Barn Swallow fledglings.

2.5

3

3.5

4

4.5

5

5.5

0 0.2 0.4 0.6 0.8

Mea

n N

umbe

r of

Fle

dglin

gs

Mean Sightings

Mean EUST

Mean PHOE

16

We found no significant differences in the number of fledglings when House Sparrows

(F2,9 = 4.41, P=0.86) were sighted in the vicinity of nests. There were also no significant

differences in number of fledglings based on colony size, although there was a slight positive

relationship (F2,9 = 4.41, P=0.42; Figure 7). The Spearman Correlation did not find a significant

correlation between number of fledglings and colony size or mean number of competitor species

sightings (Table 3).

Figure 7: Comparison of colony size and mean number of Barn Swallow fledglings.

Discussion

We found that both local and site-level factors influenced Barn Swallow nesting activities.

Our study found that increased human activity was positively associated with nest site selection

by Barn sSwallows. Initially, we believed that having low human activity would be a positive

nesting site characteristic and would lead to larger colonies or a greater chance of site selection.

2.5

3

3.5

4

4.5

5

5.5

0 2 4 6 8 10 12 14 16 18 20

Mea

n N

umbe

r of

Fle

dglin

gs

Colony Size

17

However, there was a positive relationship between selection of nesting sites and frequent human

activity. Though this relationship does not agree with our original hypothesis, it can be explained.

Barn Swallows live in man-made structures, such as stables or barns. If a stable or barn has no

human activity, it could be difficult for Barn Swallows to get into the building without humans

leaving doors and windows open. The control barns with low human activity are generally kept

closed off to wildlife. Human presence has also been linked to avian species richness, with more

densely populated areas of people correlating with more birds (Luck 2007). The presence of

more humans around a nest site could be linked to more humans being nearby to open barns.

Humans could also, whether inadvertently or purposefully, keep predators away from their

property and thus the Barn Swallow nests.

We found no relationship between nest site selection and livestock. In other studies, the

presence of livestock has been considered a positive characteristic of a location for Barn

Swallow nesting because manure of livestock has been proven to attract insect populations

(Moller 2001). Another previous study found that livestock presence does not affect nest success

for single brood nests, because for these nests, swallows select the optimal time to raise their

young; for multi-brood nests, the favorable conditions created by livestock presence allows the

multiple broods to be raised at generally less convenient times in the breeding season (Gruebler

et al. 2010). Livestock presence increases temperature in the microclimate around the nest, and

higher temperatures are useful for the multiple-brood birds, who lay earlier in the season when it

is cooler, and finish raising their last clutch later in the season when it is once again cool

(McCarty & Winkler 1999; Dawson et al. 2005).

We found that other species present in the area of Barn Swallow nests affected nest

success. European Starling sightings had a negative relationship with Barn Swallow nest success,

18

and that Eastern Phoebe sightings had a positive relationship with nest success. At Flintlock

Farm, one nest was observed being taken over by an Eastern Phoebe, and the Barn Swallow eggs

were removed, so the positive relationship in this small sample size may be attributed to habitat

quality. At the Post Office location, one of the nests was started in a European Starling nest, after

the Starlings fledged. Other studies have found high rates of nest competition between European

Starlings and other species, where the European Starlings took over 50% of the Red-Bellied

(Melanerpes carolinus) and Red-Headed (Melanerpes erythrocephalus) Woodpecker nests being

monitored (Ingold 1989). The Spearman correlation did not find a significant correlation

between number of fledglings and competitor species presence, but the relationship may still be

biologically relevant in a larger sample size.

We did not detect a significant relationship between colony size and nest success.

However, our sample size may have been too low to detect differences. In fact, sites with ≥5

nests had an average 4.5 fledglings compared to 3.6 fledglings at sites with <5 nests. Although

the Spearman correlation determined that there is no significant correlation between colony size

and number of fledglings, mean number of fledglings did increase with colony size. Shields and

Crook (1987) determined that large colonies are less successful because the birds are generally

younger, and Snap (1976) determined that larger colonies are generally more successful because

there is less predation and more social stimulation. Our data suggest that the relationship

between colony size and nest success is in fact non-linear. Mid-sized colonies appeared to have

the highest degree of nest success, which is consistent with past studies showing higher nest

success in colonies, but lower nest success in large, young colonies.

Our research did not show a relationship between Barn Swallow nest presence and

distance to field or water. In the past, research has indicated that open field space is positively

19

linked to Barn Swallow presence if livestock is also present (Henderson et al. 2007). Beyond this,

little research has been conducted specifically related to nest site proximity to bodies of water or

open field spaces. Distance to water bodies and open fields could have an impact on site

selection, because these locations are ideal habitats for insects, the food source of Barn Swallows.

If a location has a steady food supply, it might be more attractive than a location with

inconsistent or difficult to find food.

This study could be improved by adding more locations to be monitored. Because the

sample size was small, and only 10 sites with nests were monitored (20 sites were monitored

total), statistical significance was difficult to draw because of high variability due to a single year

of sampling. Because of this variability, it would be helpful to compare data from different years

because it is possible that a site had an unusually good or bad year. Finally, it would be helpful to

monitor multiple broods from the same year because other studies have found results can change

based on number of broods (Gruebler et al. 2010).

Because we had high rates of nest success, 87% overall, and observed no predation

events, we believe that the decline of Barn Swallows is caused by loss of habitat or limitation of

barn use. At several of the control locations, homeowners explained that the barns are often kept

closed to discourage Barn Swallow entry. At one active barn that had Barn Swallows, the

homeowner wanted to know if we could remove the Barn Swallows from the property because

they were considered a nuisance. Another factor that could be studied further is barn owners’

willingness to host Barn Swallows, and the effects of this on nest site selection and nest success.

At the Crooked Pond Farm location, the owners of the property screened in a particular part of

the loft of their barn and kept all windows to it shut until the start of Barn Swallow breeding

season to keep out competitor species. Their efforts to keep other species out and to attract Barn

20

Swallows back to their property may have had an influence on that location’s 100% nest success,

therefore supporting the idea that human willingness to host Barn Swallows leads to Barn

Swallow nests. An educational campaign about the benefits of Barn Swallows could lead to more

barn-owners becoming willing to host nest sites. By simply conducting our study, we were able

to educate some homeowners. At one location, the homeowners have decided to construct Barn

Swallow nesting platforms in their barn to facilitate nesting for future breeding seasons.

21

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determining the growth of nestling Tree Swallows (Tachycineta bicolor). Ibis 141.2: 286-

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24

Appendix A: Comprehensive Nest Data Table A- 1: Site locations and characteristics.

Active Locations

Harvard Falmouth

Location Saafield's Barn Location Maushop

Equestrain Center

Structure Barn Structure Barn

Address 15 Woodchuck Hill Road, Harvard, MA,

01451 Address

31 Quashnet Rd Mashpee, MA

02649

Coordinates 42.497303,-71.571829 Coordinates 41.643119, -

70.486806

Geography Description Large field, pond Geography Description Small property, Washburn Pond

nearby Human Activity 2 Human Activity 2

Location Micheldever Farm Location Coonamessett Farm

Structure Barn Structure small barn

Address 159 E Bare Hill

Road, Harvard, MA, 01451

Address 277 Hatchville

Rd East Falmouth, MA


70.575911

Geography Description Large pasture, pond Geography Description

large fields, variety of barns with a variety of

sizes Human Activity 2 Human Activity 3

Location Flintlock Farm Location Boxberry Hill Farm

Structure Barn Structure Barn

Address 327 Still River


Address 407 Boxberry Hill Rd, East

Falmouth, MA

Coordinates 42.4762692, -71.6212437 Coordinates 41.629902, -

70.569370

Geography Description Marshy area, large field Geography Description

Large property, pond near by,

large fields

Human Activity 2 Human Activity 3

Location Stable Location Smithfield Farm

Structure Barn Structure barn/indoor riding ring

Address 45 Boxboro Road, Littleton, MA Address

809 Sandwich Road East

Falmouth, MA 02536

25


70.566443

Geography Description Pastures nearby Geography Description large property, pond near by,

field


Location Post Office Location Crooked Pond Farm

Structure Building Structure Barn Loft

Address 215 Ayer Road, Harvard, MA,

01451 Address

308 Hatchville Rd, East

Falmouth, MA 02536


70.581282

Geography Description Open Fields Geography Description large field, pond nearby


Control Locations

Harvard Falmouth

Location Fruitlands Location Nyes Neck Farm

Structure Barn Structure barn

Address 98 Prospect Hill

Road, Harvard, MA 01451

Address 1 Sweet Road

North Falmouth MA


70.631076

Geography Description Large fields Geography Description

Large field with old barn on property,

surrounded by marsh


Location Dunroven Farm Location Coonamessett (Farm Storage

Shed)

Structure Barn Structure large shed/small barn

Address 62 Old Mill Road,

Harvard, MA, 01451

Address 277 Hatchville

Rd East Falmouth, MA


70.575911

Geography Description Large pasture area Geography Description large farm area, pond near by

26


Location Still River Farm Location Coonamessett

Farm (Play Shack

Structure Barn Structure

Address 203 W Bare Hill


Address 277 Hatchville Rd


70.575911

Geography Description Large pastures Geography Description Large farm area, pond near by


Location Glimerton Farm Location Old storage shed

Structure Barn Structure shed

Address 51 Boxboro Road, Littleton, MA Address 15 Grove Street


70.640181

Geography Description Large fields Geography Description Large yard, right by marsh


Location Bazarnick's House Location Grove Barn

Structure Deck Structure barn

Address 355 Old Littleton

Road, Harvard, MA 01451

Address 4 Grove Street


70.639562

Geography Description Large yard, nearby pond Geography Description

large yard, surrounded by

marsh


27

Table A- 2: Nest success descriptive data.

Location Number of

nests (sample

size)

Daily Survival

Probability (Mayfield Estimate)

Total Survival Probability

(Mayfielddays)

% Successful

Nests

Mean Days

Active/Nest

Saafield's Barn 6 1 1 100 36.17 Micheldever

Farm 5 1 1 100 37.4

Post Office 3 0.99 0.62 66.67 24 Stable 1 1 1 100 38

Flintlock Farm 18 1 0.87 83.33 42.22 Coonamessett

Farm 2 1 1 100 27 Crooked Pond

Farm 5 1 1 100 11.6

Boxberry Farm 1 1 1 100 27 Smithfield Farm 2 0.98 0.58 50 32

Maushop 12 0.99 0.76 83.33 86.11 Table A- 3: Comprehensive nest success summary.

Location Mean Nestlings

SE Nestlings

Lower Confidence

Interval (LCI)

Nestlings (95%)

Upper Confidence

Interval (UCI)

Nestlings (95%)

Mean Fledglings

SE Fledglings

LCI Fledglings

(95%)

UCI Fledglings

(95%)

Saafield's Barn 5 0.15 4.69 5.31 5 0.15 4.69 5.31

Micheldever Farm 4 0.34 3.26 4.74 4 0.34 3.26 4.74

Post Office 3.67 0.7 2.2 5.13 3.67 0.7 2.21 5.13

Stable 5 0 5 5 5 0 5 5

Flintlock Farm 4.28 0.52 3.17 5.39 4.06 0.56 2.86 5.26

Coonamessett Farm 3.5 0.25 2.91 4.09 3.5 0.25 2.91 4.09

Crooked Pond Farm 5 0.41 3.95 6.05 5 0.41 3.95 6.05

Boxberry Farm 3 0 3 3 3 0 3 3

Smithfield Farm 3 1.28 0.15 5.85 3 1.28 0.15 5.85

Maushop 4 0.67 2.47 5.53 4.33 0.7 2.74 5.92

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Table A- 4: Individual nest success.

Location Nest Label Fate # Fledglings Length of Activity (days)

Saafield's Barn A Successful 5 38 Saafield's Barn B Successful 5 38 Saafield's Barn C Successful 4 38 Saafield's Barn D Successful 6 38 Saafield's Barn E Successful 5 34 Saafield's Barn I Successful 5 31

Micheldever Farm A Successful 4 36 Micheldever Farm B Successful 2 38 Micheldever Farm C Successful 4 36 Micheldever Farm D Successful 5 34 Micheldever Farm E Successful 5 43

Post Office A Failed 0 9 Post Office B Successful 6 33 Post Office C Successful 5 30

Stable A Successful 5 38 Flintlock Farm A Failed 0 27 Flintlock Farm F Successful 2 40 Flintlock Farm G Successful 5 44 Flintlock Farm H Failed 0 39 Flintlock Farm I Successful 5 43 Flintlock Farm K Successful 5 48 Flintlock Farm M Successful 5 44 Flintlock Farm N Successful 6 48 Flintlock Farm O Successful 5 39 Flintlock Farm Q Successful 6 44 Flintlock Farm T Successful 6 44 Flintlock Farm W Successful 4 48 Flintlock Farm Z Successful 4 44 Flintlock Farm DD Successful 5 48 Flintlock Farm FF Failed 0 39 Flintlock Farm II Successful 5 39 Flintlock Farm JJ Successful 6 39 Flintlock Farm NN Successful 4 43

Coonamessett Farm A Successful 4 27 Coonamessett Farm B Successful 3 27 Crooked Pond Farm A Successful 4 12 Crooked Pond Farm C Successful 6 12 Crooked Pond Farm G Successful 6 12

29

Crooked Pond Farm L Successful 4 11 Crooked Pond Farm R Successful 5 11

Boxberry Farm A Successful 3 27 Smithfield Farm A Failed 0 51 Smithfield Farm B Successful 6 13

Maushop A Successful 6 18 Maushop B Successful 5 24 Maushop C Successful 5 26 Maushop D Successful 4 21 Maushop E Failed 0 0 Maushop F Failed 0 16 Maushop G Successful 4 21 Maushop H Successful 6 21 Maushop I Successful 6 26 Maushop J Successful 7 26 Maushop K Successful 4 26 Maushop L Successful 5 28

30

Appendix B: Comprehensive Descriptive Statistics Table B- 1: Visit summary descriptive statistics.

Location

Days Active

(Sample Size)

Mean Swallows

SE Swallows

LCI (95%)

UCI (95%)

Mean HOSP

SE HOSP

LCI HOSP (95%)

UCI HOSP (95%)

Saafield's Barn 18 18.24 1.1 15.92 20.56 0.39 0.14 0.09 0.69 Micheldever

Farm 13 11.38 0.53 10.23 12.53 5.36 0.9 3.4 7.32

Post Office 21 2.33 0.33 1.63 3.03 0.05 0.05 -0.05 0.15 Stable 13 2 0.23 1.51 2.49 1.85 0.68 0.37 3.33

Flintlock Farm 14 58.57 0.97 56.49 60.65 0 0 0 0 Coonamessett

Farm 8 3.88 0.52 2.66 5.1 12.38 1 10.02 14.74

Crooked Pond Farm 6 7 0.52 5.67 8.33 0 0 0 0

Boxberry Farm 9 2.22 0.28 1.58 2.86 3.11 0.35 2.3 3.92 Smithfield Farm 11 3.09 0.61 1.73 4.45 4.09 0.37 3.27 4.91

Maushop 10 16.9 1.23 14.11 19.69 10.7 0.9 8.68 12.72 Dunroven Farm 3 0 0 0 0 3.33 0.88 -0.46 7.12

Fruitlands 3 0 0 0 0 1.67 0.88 -2.12 5.46 Still River Farm 3 0 0 0 0 1 1 -3.3 5.3 Glimerton Farm 3 0.33 0 0.33 0.33 11.67 0.88 7.88 15.46

Bazarnick's House 3 0 0.33 -1.43 1.43 1.33 0.88 -2.46 5.12

Nyes Neck Farm 3 0 0 0 0 3.67 0.88 -0.12 7.46

Grove Barn 3 0 0 0 0 2.33 1.45 -3.92 8.58 Old Storage

Shed 3 0 0 0 0 1 0.58 -1.48 3.48

Farm Storage Shed 3 2.66 0.88 -1.13 6.45 10.33 0.88 6.54 14.12

Play Shack 3 4 0.58 1.52 6.48 12.67 1.2 7.5 17.84

31

Table B- 2: Additional visit summary statistics.

Location Mean EUST SE EUST

LCI EUST (95%)

UCI EUST (95%)

Mean PHOE

SE PHOE

LCI PHOE (95%)

UCI PHOE (95%)

Saafield's Barn 0.06 0.06 -0.06 0.18 0.67 0.27 0.1 1.24 Micheldever

Farm 0 0 0 0 0.64 0.32 -0.06 1.34

Post Office 0.24 0.17 -0.11 0.59 0 0 0 0 Stable 0 0 0 0 0 0 0 0

Flintlock Farm 0 0 0 0 0.07 0.07 -0.08 0.22 Coonamessett

Farm 0.75 0.53 -0.49 1.99 0.25 0.25 -0.34 0.84

Crooked Pond Farm 0 0 0 0 0 0 0 0

Boxberry Farm 0 0 0 0 0 0 0 0 Smithfield Farm 0 0 0 0 0 0 0 0

Maushop 0 0 0 0 0 0 0 0 Dunroven Farm 0 0 0 0 1 0.58 -1.48 3.48

Fruitlands 0 0 0 0 0 0 0 0 Still River Farm 0 0 0 0 0.33 0.33 -1.1 1.76 Glimerton Farm 0 0 0 0 0.33 0.33 -1.1 1.76

Bazarnick's House 0 0 0 0 0 0 0 0

Nyes Neck Farm 0 0 0 0 0 0 0 0

Grove Barn 0 0 0 0 0 0 0 0 Old Storage

Shed 0 0 0 0 0 0 0 0

Farm Storage Shed 0 0 0 0 0 0 0 0

Play Shack 0 0 0 0 0 0 0 0

32

Table B- 3: Visit summary predator sighting statistics.

Location Mean Cat

SE Cat

LCI Cat

(95%)

UCI Cat

(95%)

Mean Hawk

SE Hawk

LCI Hawk (95%)

UCI Hawk (95%)

Mean Dog

SE Dog

LCI Dog

(95%)

UCI Dog

(95%) Saafield's

Barn 0 0 0 0 0 0 0 0 0 0 0 0

Micheldever Farm 0 0 0 0 0 0 0 0 1 0 1 1

Post Office 0 0 0 0 0 0 0 0 0 0 0 0

Stable 4.77 0.52 3.63 5.9 0 0 0 0 0 0 0 0

Flintlock Farm 0 0 0 0 0 0 0 0 0 0 0 0

Coonamessett Farm 0 0 0 0 0 0 0 0 0 0 0 0

Crooked Pond Farm 0 0 0 0 0 0 0 0 0 0 0 0

Boxberry Farm 0.78 0.32 0.03 1.52 0 0 0 0 0.78 0.32 0.03 1.52

Smithfield Farm 0.18 0.18 -0.22 0.59 0 0 0 0 2.27 0.38 1.42 3.13

Maushop 0 0 0 0 0 0 0 0 1.4 0.4 0.5 2.3

Dunroven Farm 0 0 0 0 0.33 0.33 -1.1 1.77 4 0 4 4

Fruitlands 0 0 0 0 0.33 0.33 -1.1 1.77 0 0 0 0

Still River Farm 1.33 0.67 -1.54 4.2 0 0 0 0 0 0 0 0

Glimerton Farm 0.67 0.33 -0.77 2.1 0 0 0 0 0 0 0 0

Bazarnick's House 0 0 0 0 0 0 0 0 0 0 0 0

Nyes Neck Farm 1.67 0.33 0.23 3.1 0.33 0.33 -1.1 1.77 0 0 0 0

Grove Barn 1.33 0.67 -1.54 4.2 0.33 0.33 -1.1 1.77 0 0 0 0

Old Storage Shed 1 0.58 -1.48 3.48 0.33 0.33 -1.1 1.77 0 0 0 0

Farm Storage Shed 0 0 0 0 0 0 0 0 0 0 0 0

Play Shack 0 0 0 0 0 0 0 0 0 0 0 0

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